1. Field of the Invention
The present invention relates to an endoscope of a drive source unit separable type that is provided with a drive source unit separably coupled to a distal end section of an insertion section of the endoscope via a separable section, where drive force generating means for operating a bending section disposed on a distal end side of the insertion section in a bending manner is incorporated in the drive source unit.
2. Description of the Related Art
Jpn. Pat. Appln. KOKAI Publications No. 2000-14628 (Patent Document 1) discloses one example of endoscope apparatus of a separable type. In the endoscope apparatus of a separable type, an insertion section of an endoscope and an operation section on a near side disposed at a proximal end section of the insertion section are separably coupled to each other via a separable section. The insertion section of the endoscope includes a bending section deformable in a bending manner disposed between a section comprising a slender soft section and a distal end section thereof. An operation knob of a bending operation mechanism for operating the bending section in a bending manner is provided on the operation section.
Distal end sections of four wire cables for performing a bending operation are fixed to a distal end section of the bending section. Proximal end sections of the wire cables extend toward the proximal end section of the insertion section. A transmission mechanism for transmitting a driving force to be transmitted from the operation knob to the bending section is disposed on the proximal end section of the insertion section. The transmission mechanism includes guide wheels reversing directions of the four wire cables and passive shafts. Proximal end sections of the wire cables are coupled to the passive shafts via the guide wheels.
A pinion is fixed to a drive shaft of the operation knob of the operation section. A pair of racks meshes with the pinion such that the racks face each other, and the drive shaft is provided in its state coupled to the racks. Such a configuration is adopted that, when the proximal end section of the insertion section of the endoscope and the operation section are coupled to each other via a separable section, the drive shaft and the passive shaft are caused to abut on each other, so that bending operation is performed according to advancing and retreating of the passive shaft.
Jpn. Pat. Appln. KOKAI Publications No. H6-114001 (Patent Document 2) discloses an endoscope apparatus having a configuration where a bending-drive source for driving a bending section of an endoscope is provided separately from a main body of the endoscope, and the endoscope and the bending-drive source are separably coupled to each other. Here, a driving force orthogonally-converting mechanism utilizing a bevel gear is provided in the endoscope. Further, an input shaft on the side of the endoscope and an output shaft on the side of the bending-drive source are separably coupled in a coaxial manner. Bending operation of the bending section of the endoscope is performed by a driving force from the bending-drive source during a coupling between the endoscope and the bending-drive source.